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/*
* July 5, 1991
* Copyright 1991 Lance Norskog And Sundry Contributors
* This source code is freely redistributable and may be used for
* any purpose. This copyright notice must be maintained.
* Lance Norskog And Sundry Contributors are not responsible for
* the consequences of using this software.
*/
/*
* Sound Tools Sound Blaster VOC handler sources.
*
* Outstanding problem: the Sound Blaster DMA clock is 8 bits wide,
* giving spotty resolution above 10khz. voctartwrite() should check
* the given output rate and make sure it's +-1% what the SB can
* actually do. Other format drivers should do similar checks.
*
* June 28, 93: force output to mono.
*/
#include "st.h"
/* Private data for VOC file */
typedef struct vocstuff {
long rest; /* bytes remaining in current block */
long rate; /* rate code (byte) of this chunk */
int silent; /* sound or silence? */
long srate; /* rate code (byte) of silence */
int blockseek; /* start of current output block */
long samples; /* number of samples output */
} *vs_t;
#define VOC_TERM 0
#define VOC_DATA 1
#define VOC_CONT 2
#define VOC_SILENCE 3
#define VOC_MARKER 4
#define VOC_TEXT 5
#define VOC_LOOP 6
#define VOC_LOOPEND 7
#define min(a, b) (((a) < (b)) ? (a) : (b))
IMPORT int summary, verbose;
void getblock();
vocstartread(ft)
ft_t ft;
{
char header[20];
vs_t v = (vs_t) ft->priv;
int sbseek;
if (! ft->seekable)
fail("VOC input file must be a file, not a pipe");
if (fread(header, 1, 20, ft->fp) != 20)
fail("unexpected EOF in VOC header");
if (strncmp(header, "Creative Voice File\032", 19))
fail("VOC file header incorrect");
sbseek = rlshort(ft);
fseek(ft->fp, sbseek, 0);
v->rate = -1;
v->rest = 0;
getblock(ft);
if (v->rate == -1)
fail("Input .voc file had no sound!");
ft->info.rate = 1000000.0/(256 - v->rate);
ft->info.size = BYTE;
ft->info.style = UNSIGNED;
if (ft->info.channels == -1)
ft->info.channels = 1;
}
vocread(ft, buf, len)
ft_t ft;
long *buf, len;
{
vs_t v = (vs_t) ft->priv;
int done = 0;
if (v->rest == 0)
getblock(ft);
if (v->rest == 0)
return 0;
if (v->silent) {
/* Fill in silence */
for(;v->rest && (done < len); v->rest--, done++)
*buf++ = 0x80000000;
} else {
for(;v->rest && (done < len); v->rest--, done++) {
long l;
if ((l = getc(ft->fp)) == EOF) {
fail("VOC input: short file"); /* */
v->rest = 0;
return 0;
}
l ^= 0x80; /* convert to signed */
*buf++ = LEFT(l, 24);
}
}
return done;
}
/* nothing to do */
vocstopread(ft)
ft_t ft;
{
}
vocstartwrite(ft)
ft_t ft;
{
vs_t v = (vs_t) ft->priv;
if (! ft->seekable)
fail("Output .voc file must be a file, not a pipe");
v->samples = 0;
/* File format name and a ^Z (aborts printing under DOS) */
(void) fwrite("Creative Voice File\032\032", 1, 20, ft->fp);
wlshort(ft, 26); /* size of header */
wlshort(ft, 0x10a); /* major/minor version number */
wlshort(ft, 0x1129); /* checksum of version number */
ft->info.size = BYTE;
ft->info.style = UNSIGNED;
if (ft->info.channels == -1)
ft->info.channels = 1;
else /* Don't implement stereo yet! */
ft->info.channels = 1;
}
vocwrite(ft, buf, len)
ft_t ft;
long *buf, len;
{
vs_t v = (vs_t) ft->priv;
unsigned char uc;
v->rate = 256 - (1000000.0/(float)ft->info.rate); /* Rate code */
if (v->samples == 0) {
/* No silence packing yet. */
v->silent = 0;
blockstart(&outformat);
}
v->samples += len;
while(len--) {
uc = RIGHT(*buf++, 24);
uc ^= 0x80;
putc(uc, ft->fp);
}
}
vocstopwrite(ft)
ft_t ft;
{
blockstop(ft);
}
/* Voc-file handlers */
/* Read next block header, save info, leave position at start of data */
void
getblock(ft)
ft_t ft;
{
vs_t v = (vs_t) ft->priv;
unsigned char uc, block;
unsigned long sblen;
int i;
v->silent = 0;
while (v->rest == 0) {
if (feof(ft->fp))
return;
block = getc(ft->fp);
if (block == VOC_TERM)
return;
if (feof(ft->fp))
return;
uc = getc(ft->fp);
sblen = uc;
uc = getc(ft->fp);
sblen |= ((long) uc) << 8;
uc = getc(ft->fp);
sblen |= ((long) uc) << 16;
switch(block) {
case VOC_DATA:
uc = getc(ft->fp);
if (uc == 0)
fail("File %s: Sample rate is zero?");
if ((v->rate != -1) && (uc != v->rate))
fail("File %s: sample rate codes differ: %d != %d",
v->rate, uc);
v->rate = uc;
uc = getc(ft->fp);
if (uc != 0)
fail("File %s: only interpret 8-bit data!");
v->rest = sblen - 2;
return;
case VOC_CONT:
v->rest = sblen;
return;
case VOC_SILENCE:
{
unsigned short period;
period = rlshort(ft);
uc = getc(ft->fp);
if (uc == 0)
fail("File %s: Silence sample rate is zero");
/*
* Some silence-packed files have gratuitously
* different sample rate codes in silence.
* Adjust period.
*/
if ((v->rate != -1) && (uc != v->rate))
period = (period * (256 - uc))/(256 - v->rate);
else
v->rate = uc;
v->rest = period;
v->silent = 1;
return;
}
case VOC_MARKER:
uc = getc(ft->fp);
uc = getc(ft->fp);
/* Falling! Falling! */
case VOC_TEXT:
{
int i;
/* Could add to comment in SF? */
for(i = 0; i < sblen; i++)
getc(ft->fp);
}
continue; /* get next block */
case VOC_LOOP:
case VOC_LOOPEND:
report("File %s: skipping repeat loop");
for(i = 0; i < sblen; i++)
getc(ft->fp);
break;
default:
report("File %s: skipping unknown block code %d",
ft->filename, block);
for(i = 0; i < sblen; i++)
getc(ft->fp);
}
}
}
/* Start an output block. */
blockstart(ft)
ft_t ft;
{
vs_t v = (vs_t) ft->priv;
v->blockseek = ftell(ft->fp);
if (v->silent) {
putc(VOC_SILENCE, ft->fp); /* Silence block code */
putc(0, ft->fp); /* Period length */
putc(0, ft->fp); /* Period length */
putc((int) v->rate, ft->fp); /* Rate code */
} else {
putc(VOC_DATA, ft->fp); /* Voice Data block code */
putc(0, ft->fp); /* block length (for now) */
putc(0, ft->fp); /* block length (for now) */
putc(0, ft->fp); /* block length (for now) */
putc((int) v->rate, ft->fp); /* Rate code */
putc(0, ft->fp); /* 8-bit raw data */
}
}
/* End the current data or silence block. */
blockstop(ft)
ft_t ft;
{
vs_t v = (vs_t) ft->priv;
long datum;
putc(0, ft->fp); /* End of file block code */
fseek(ft->fp, v->blockseek, 0); /* seek back to block length */
fseek(ft->fp, 1, 1); /* seek forward one */
if (v->silent) {
datum = (v->samples) & 0xff;
putc((int)datum, ft->fp); /* low byte of length */
datum = (v->samples >> 8) & 0xff;
putc((int)datum, ft->fp); /* high byte of length */
} else {
v->samples += 2; /* adjustment: SBDK pp. 3-5 */
datum = (v->samples) & 0xff;
putc((int)datum, ft->fp); /* low byte of length */
datum = (v->samples >> 8) & 0xff;
putc((int)datum, ft->fp); /* middle byte of length */
datum = (v->samples >> 16) & 0xff;
putc((int)datum, ft->fp); /* high byte of length */
}
}
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